Offer it in colors that are actually darker than the screen (as they did with the 900) and make accessories available for the entire life-cycle of the device (as they did with the 900 -- you can still buy the lighted case).

Also, allow 3G for all net-related activities, as Amazon does, not just for purchases from the Sony Store. Add a faster processor and, when the obsolescence cycle allows, a higher-resolution screen. I say that not because I'm used to looking at computer screens but because I appreciate fonts in a higher dpi on the printed page. They're more satisfying and seem easier to read.

I would like to see smoothly variable font sizes instead the current stepped size. After all this is the whole point of outline fonts.

Colour eink would be nice (you will never get the brightness range that you get from backlit lcd. It can't be done. It's impossible. The best you will ever get is something that looks like colour printing on coated newsprint -- I'd love it!)

3G or any other cell phone connectivity is a negative feature for me.

Wifi is not something that I would regard as a feature and certainly would not pay extra for.

A six inch screen. The pocket edition is nice, it very pocketable and easy to read. It still prefer the 6" screen. a 7" screen (4:3) would be nice if the device was a small a possible -- like the 650 but just that much bigger to accommodate the larger screen.

And best of all, a Canadian price no more than 20% higher that the Kobo Touch (Future Shop is still selling the 350 for $200.)